How does a sourdough sponge work?
I'm trying to learn more about sponges in breadmaking.
Most recipes that I've found for sourdough bread don't use a sponge. What does it add?
Also, what's a general rule of thumb for how to make one? From what I can gather, it looks like the sponge is just an extra-large batch of starter. By this, what I mean is: I refresh my starter with 50g water, 50g flour. It looks like sponges are essentially equivalent to refreshing a starter with 300g (or whatever) of each. Then the next day, you add some more dry flour until you get something solid enough to work with. Is this the gist of a sponge? If so, wouldn't the sourdough break down the gluten in the sponge, thereby greatly reducing the amount in the final product that you have to work with?
Best Answer
A lot of sourdough recipes don't call for a sponge, per se, because the starter essentially already is a sponge. The purpose of a sponge in a bread with normal yeast is to allow a longer fermentation time and extra time for enzymatic reactions to happen in the flour before adding it to the final batch. This isn't necessary with sourdough the starter is continuously fermenting and reacting.
And your guess is about right, if the proportion of starter you add is too high, the waste products and dead yeast cells in it can cause changes in the gluten that make it very slack and unusable.
Pictures about "How does a sourdough sponge work?"
What is the sponge in sourdough?
A sponge is just as it sounds: a bubbled mixture of flour, water and a touch of yeast. For a rather low-rent approach, it produces rather phenomenal results: a crust and flavor like sourdough, with less of the taste that some sourdough haters can do without, due to shortened pre-fermentation.What is the difference between a sponge and a sourdough starter?
Sourdough starter is used to add flavor to bread and to leaven it slowly and naturally. A sponge is the first stage of mixing bread dough in which yeast, liquid and approximately half of the flour in the formula is mixed to make a thick, wet dough.How long should you leave sourdough sponge?
Step 2: Leave it on the counter top for 12 hours (give or take a few hours depending on the room's temperature). It should at this point show signs of activity i.e. bubbles, growth. If it doesn't, don't worry, keep feeding it at regular intervals according to your usual schedule, until you see life in it again.How do you feed a sourdough sponge?
Add 1 scant cup (113g) flour and 1/2 cup (113g) lukewarm water to the 1/2 cup (113g) starter in the bowl. Mix until smooth and cover. Allow the starter to rest at room temperature (about 70\xb0F) for at least 2 hours; this gives the yeast a chance to warm up and get feeding.The science behind sourdough
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